TC1303B-ZA0EUN

Overview

The TC1303B-ZA0EUN is a dual-output power management integrated circuit manufactured by Microchip Technology. It integrates a 500 mA synchronous buck regulator and a 300 mA low-dropout (LDO) linear regulator within a single package. The device operates with an input voltage range of 2.7 V to 5.5 V. The buck converter supports a fixed switching frequency of 2.0 MHz and features automatic transition from pulse width modulation (PWM) to pulse frequency modulation (PFM) modes for optimized efficiency across varying load conditions. The LDO output provides independent shutdown capability. Both regulators are internally compensated, and the device includes a power-good output signal with a 300 ms delay. Total quiescent current is typically 65 µA.

Feature Summary

• Integrates a 500 mA synchronous buck regulator and a 300 mA low-dropout linear regulator in a single compact package.
• Features automatic transition between PWM and PFM modes to maintain high efficiency under heavy and light load conditions.
• Provides independent shutdown control for both the buck and LDO outputs to manage system power states.
• Includes a power-good output indicator with a defined delay time to signal stable regulation status.

Applications

• Portable battery-powered consumer electronics requiring multiple regulated voltage rails
• Embedded systems utilizing single-cell lithium-ion or lithium-polymer batteries
• Industrial control modules needing efficient step-down conversion with low noise
• Wireless communication devices requiring low quiescent current operation

Procurement Notes

Verify the specific suffix ZA0EUN against official Microchip documentation to confirm pinout compatibility and output voltage configuration. Ensure the ordering information matches the required tape-and-reel packaging specifications. Cross-reference the manufacturer part number with authorized distributors to confirm authenticity and traceability. Check for any recent product change notices that may affect mechanical dimensions or electrical characteristics prior to final procurement approval.

Selection Notes

Select this component when a design requires two distinct regulated outputs from a single power source with minimal external component count. The integrated synchronous buck offers higher efficiency compared to standard inductor-based solutions, while the LDO provides clean power for sensitive analog circuits. Consider the 2.0 MHz switching frequency for smaller passive components. Verify that the total output current requirements do not exceed the 500 mA buck and 300 mA LDO limits simultaneously under worst-case thermal conditions.

Part Context

This device belongs to the TC1303 family of dual-output regulators from Microchip Technology. The family variants differ primarily in output voltage configurations and package types. The TC1303B specifically denotes the version with a 500 mA buck and 300 mA LDO. Related parts include the TC1303A and TC1303C, which share similar functional architectures but may vary in specific electrical parameters or available output voltages. The ZA0EUN suffix indicates a specific output voltage setting and MSOP-10 packaging.

Replacement Considerations

Direct substitutes within the same family include TC1303B-SA0EMFTR and other TC1303B variants with compatible output voltages. Verify pin-to-pin compatibility and ensure the replacement part supports the required input voltage range and output current capabilities. Review datasheet differences regarding thermal performance and switching frequency if modifying the design layout.